


Falling Slowly

by HPfanonezillion



Category: The Dark Artifices Series - Cassandra Clare, The Shadowhunter Chronicles - Cassandra Clare
Genre: Black Rose Triad, College AU, F/M, Kierarktina, M/M, Multi, Other, Polyamory, internship AU
Language: English
Status: In-Progress
Published: 2017-06-28
Updated: 2017-07-05
Packaged: 2018-11-20 00:11:57
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 3,029
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11324622
Author URL: https://archiveofourown.org/users/HPfanonezillion/pseuds/HPfanonezillion
Summary: Cristina and Mark are growing really close in their social worker internship when Mark's former boyfriend Kieran joins the office. Cristina realizes Mark still has feelings for Kieran, but she finds she doesn't feel any jealousy.





	1. Prologue

**Notes for the Chapter:**

> I LOVE the thought of Kieran, Mark, and Cristina together! And with all the angst in Lord of Shadows, I wanted something a little light. Even though the first bit is a little heavy, a majority of this will be light and fluffy and fun.
> 
> The title comes from the song of the same name from the movie Once.
> 
> Much thanks to my bestie writingbutunpublished for helping me come up with ideas for this story. You should go read her stuff!
> 
> Happy reading!

Mark sat at the kitchen table with Helen and Julian. Both had matching looks of worry. Mark knew his own face wore the same expression looking back at them.

Helen twirled her wedding band around her finger and looked out to the dark sky beyond the patio doors. "Aline and I can't take all four of them on. We don't have the space." She said softly. "And even if we did, it wouldn't be a good thing to uproot them all, especially Ty. He needs his routine." She looked to her younger brothers. "I can talk to Aline about moving closer, but—"

Julian cut her off. "Your research, Helen. You can't abandon the research."

Helen waved her hand. "It's just allowing someone else to take the credit." Helen looked directly at Julian. "But you want them, don't you?"

"Yes." Julian glanced toward Mark.

He was still silent. Mark was in no position to take on the kids. He was still in college, living with his sometime-boyfriend Kieran, and partying. He couldn't possibly take on four kids. He didn't even have a real job.

"Mark, what do you think?" Helen asked.

Mark swallowed. "Julian has the gym. Julian has the house. Julian should have custody of the kids. He's been groomed to it for years. Long before we were ever in the picture." He stood and walked out of the room toward the stairs before either of them could speak again.

He looked in on each of the kids before stepping into his own room. His phone lit up with a text as he walked toward the bed. A text from Kieran.

_When are you coming back? I miss you._

"Right, I'm sure." Mark mumbled as he typed out his reply. _Soon, Kier._

Not soon enough. He loved his family, but Kieran was more home lately. Even when they were in the off-again portion of their relationship.

Julian knocked on the door and leaned against the frame. "You could make a case for them if you want."

Mark shook his head. "They're yours, Jules. They've always been yours. I wasn't even around until a few years ago. I really don't have a claim to any of this."

"You're still a Blackthorn, Mark." Julian walked into the room. "You're still their brother."

"I am." Mark sighed. "I just can't take them. I've still got a semester of school and I have to have an internship before I'm even considered for any jobs. And it's like Helen said, Ty needs his routine. They all do. Now more than ever."

"Thank you, Mark." Julian looked toward the hall and then moved forward. "Do you think it would make any difference with a judge if I married Emma?"

Mark smiled at his brother. "You are the most stable thing to them, Julian. And so is Emma. You were already making plans to marry her, so you might as well. It would show your effort to the court."

"You really are going to be great at this, Mark." Julian squeezed his arm. "Are you going to be okay?"

Mark took in a deep breath and let it out slowly. "I am. Are you?"

Julian shrugged. "I'll have the kids and the gym to distract me." He smiled sadly. "And Emma." He looked his brother over. "I hope you have someone, Mark."

With a shrug, Mark looked at his vibrating phone.

**Kieran:** _Mark, I'm bored!_

Mark put his phone down without answering. He looked up to Julian. "Your parents were very proud of you, Jules. I know they were."

" _Our_ parents were proud of you too, Mark." Julian walked out of the room, pausing at the door. "I know you have to get back to school, but I hope this won't keep you away more than before."

"I'll be around as much as I can. I promise." Mark gave his brother a reassuring smile. "You're not getting rid of me so easily, Julian."

"And I don't want to, Mark." With one last look, Julian left.

Mark picked up his phone and wrote his reply to Kieran. _Bored and horny are two different things, Kieran. Be honest._

Kieran's response was a picture of his face looking bored. _Boredom written all over my pretty face._

**Mark:** _It is a pretty face. And I wish it were here kissing me right now._

**Kieran:** _I could be there in just a few hours. If you really mean that._

Mark considered it a moment and then typed out his reply. _Best if you don't. I'll be back in a few days._

He started getting ready for bed. His phone went off again as he was settling against his pillows. He opened it to find a picture of Kieran standing in front of the huge mirrors that adorned two walls in his massive bathroom. He was completely naked with a smirk on his face.

The accompanying text read, _In case you forget what I look like._

Mark let out a loud laugh, covering his mouth quickly to muffle the sound before he woke his siblings. He typed out, _You are magnificent, Kier. I cannot wait to get my hands on you again._

He opened up the picture and placed his phone on the pillow beside him. He stared at Kieran's perfect figure until his eyes drooped closed.


	2. Chapter One

**Notes for the Chapter:**

> I wrote this chapter twice! The first time it was so hard that it took nearly all day to get words out. And then my beta/bestie writingbutunpublished gave me some notes and I decided to scrap that and start over.
> 
> So I hope you like the direction I'm going with this. I'd love to hear your thoughts!
> 
> Happy reading!

Mark stepped into the kitchen to the normal ruckus of breakfast. Emma was already at the gym for the morning, so Julian handled getting the kids fed and where they needed to go. Since the twins had recently celebrated their sixteenth birthday and passed their driving tests, they were able to take on a bit of the school shuffle.

"Mark, don't leave without breakfast." Jules called from the stove. He passed more pancakes out.

"I'm not hungry." Mark lied as he filled his travel mug with coffee.

"Take a banana." Dru pleaded.

Mark smiled at his youngest sister and kissed the top of her head as he took the offered fruit. "Have fun at your first day of school."

Dru made a face.

Tavvy threw himself off the stool he sat on and wrapped his arms around Mark's waist. "I'll miss you."

Mark stuffed the banana into his pocket and rubbed Tavvy's back. "I'll be back not long after you get home from school."

Tavvy looked up. "Promise?"

"Promise." Mark kissed his forehead. "Ty, don't give your teachers a hard time."

Ty pulled his earphones out. "They're the ones that give  _me_  a hard time."

Mark squeezed his shoulder. "Then don't let them." He ruffled Livvy's hair. "See ya later."

"Hey!" Livvy reached up and quickly fixed her hair. "It took me nearly thirty minutes to get that perfect."

"Sorry." Mark kissed her cheek.

"Have a good one, Jules." Mark turned to head out the door, but Julian stopped him. The two shared a bear hug.

"I'm so glad you're home, Mark." Jules stepped back. "Have a good first day. Don't forget to call Emma for your pep talk."

Mark nodded. "Bye, everyone!" He called as he finally left. He was followed by a chorus of farewells. He pulled up Emma's number before he backed out of the driveway.

Emma picked up on the third ring. "Mark! You're going to do great today!" She said in greeting.

Mark laughed. "You really think so?"

"I know so." Emma said. "Because you are Mark Antony Blackthorn and you are fucking awesome!"

Mark could feel his nerves melting away. "Thank you, Emma. You're just what I need, you know?"

"I do know. I almost stayed home so I could tell you in person. And give you a big smooch."

"You're married." Mark said.

"I did harbor a bit of a crush on you, though." Emma admitted. "When Jules and I were still just friends. But I realized you're too much man for me. I'll take my Julian any day."

"You very nearly took him in front of everyone at your wedding." Mark said.

It was Emma's turn to laugh. "It's how I give comfort. We were both in a weird place then."

Mark pulled into the parking lot of the adoption center and sighed. "I'm here. Keep sending those good vibes."

"I will. I love you, Mark. And I know you'll do great."

Mark was shown to his desk and found it already occupied by a pretty girl with dark hair. She looked up with smiling brown eyes.

"This is Cristina." The supervisor said. "You two will be working together."

Mark held out his hand after a moment. "Mark. Nice to meet you."

"Likewise." Cristina said.

They had just enough time to put their few personal things away before all the interns were gathered for a tour of the facility.

"What made you want to do social work?" Cristina asked. She had a slight accent. It was nice.

"Lots of things." Mark replied. "What about you?"

"I like to help people." Cristina said with a smile. "It's very important to me."

Mark wanted to tell her everything and it frightened him a little that she made him feel that way.

That afternoon, Mark asked Cristina, "Would you like to go get a bite to eat?"

"No, I can't." Cristina said. "I just got this membership to a gym and I promised myself that I would go every day after work to make it worth it."

"Well, that's good. Then I guess I'll see you in the morning." Mark offered.

"See you in the morning." She slipped into her car and drove away.

"Should have asked what gym." He sighed and rubbed his face. "Whatever."

Mark arrived home just as Emma pulled in. She ran over and looked up expectantly.

"I met a girl." He said.

"All right. Time to get over that arrogant Kieran." Emma slipped her arm through his and walked toward the front of the house. "Tell me all about her."

* * *

Cristina walked over to Mark as soon as she stepped into the office. "Your family owns a gym?"

Mark was not expecting that sort of greeting. "Um…"

"You were part of a picture in the foyer of this gym." She said. "I  _thought_  I recognized you yesterday."

"Yeah, that's my brother's venture. Inherited from our parents." Mark gave her a sly grin. "Am I forgiven for not being forward with that information?"

Cristina considered it a moment and then nodded. "It would be nice to get a friends and family discount, though." She said with a grin of her own.

He laughed. "I'll see what I can conjure." He promised with a wink.

That evening, Mark accompanied Cristina to the gym. She outran him on the treadmill and he bought her a smoothie at the juice bar to make up for it.

"Put it on my tab, Livvy." He said to his sister as she started making the drinks.

Livvy rolled her eyes. "A tip would be nice, at least." She slid the glasses across the counter.

Mark patted his hips. "No pockets, sis." He leaned over the counter. "I'll give you five bucks when you get home."

"You better." Livvy said.

"Mark!" Tavvy called as he hurried across the room and threw himself at his brother.

"Hi, Tav. What are you doing here?" Mark said, pulling the boy onto his lap.

Emma and Dru were a few steps behind. Emma explained, "Ty had Kit over and I decided to be merciful." She draped her arm around Dru's shoulders. "So Dru gets to help Livvy here at the juice bar and Tavvy gets to sit behind the desk with me and Julian and stay out of the way."

"At least Tavvy gets to play your phone." Dru grumbled.

"Tavvy is also eight. Not quite so illegal to have a fourteen-year-old do a little work at a family business." Emma rubbed her back. "I'll make sure you're compensated."

"I could have watched Tavvy at home." Dru sauntered behind the counter.

"Sorry, don't trust you enough for that one yet." Julian said. "Barely trust Ty and Livvy." He held out his hand to Tavvy. "Come on, Tavs, let's get you settled before the evening crowd starts coming."

"Aren't you going home, Mark?" Dru asked.

"Mark's on a  _date_." Livvy said.

"It's not a date." Mark quickly tried to explain, cutting his eyes to Cristina.

That's when everyone finally noticed Cristina and started asking her questions.

Julian was the one that stepped in. "Give the man some space. We have work to do."

"Okay,  _Dad_." Dru said as she turned to the latest customer.

Emma leaned close and whispered something to Jules that made him clear his throat. "Well, I'll hold you to that." He led Tavvy to the front of the gym.

"I'll be going home shortly." Mark said to Emma. "I can take Tavvy with me."

Emma nodded. "Thanks."

The rest of the Blackthorns finally left Mark and Cristina alone.

"I'm sorry about that." Mark said softly.

Cristina shook her head. "It is no trouble. I like big families."

"That's good to know." He sipped his smoothie. "So can I spot you again tomorrow?"

She nodded. "Sure." She gave him a smile. "I have to get strong."

"Why?" Mark asked.

"To beat you, of course." She laughed and finished off her smoothie. "Thanks for this. I'll see you tomorrow."

Mark watched her leave.

Dru leaned over the counter. "Please take me with you, Mark."

With a laugh, Mark stood. "I'll ask Emma and Julian to give you a reprieve." He walked toward the reception desk.

* * *

Cristina started spending as much time with the Blackthorns as she did at the gym and the adoption center.

Mark loved how comfortable Cristina was with everyone. He also liked the soft kisses he shared with her when he dropped her off at her apartment every evening. He wanted more, but he wasn't sure how to approach it.

Thankfully, he didn't have to.

They toweled the sweat from their necks after their latest run. Cristina moved closer and whispered, "Want to go back to my place and shower?"

Mark smirked and looked around. "My shower's bigger. And the house should be empty." He stepped away and packed up his things.

She followed suit.

"Is it ever this quiet here?" Cristina asked as they paused in the silent front hall.

Mark chuckled. "Not often. Jules snores. Ty talks in his sleep. Dru and Tavvy sometimes sleepwalk." He slipped his hand into hers and led her up the stairs. "You can change your mind."

"So can you." She said as she followed in his wake.

"I don't want to." Mark adjusted the temperature of the shower. "What do you think?"

Cristina stuck her hand under the spray. "Perfect."

Mark stepped forward and peeled the sweat soaked tank top from her body. He dropped it to the floor as she reached for his shirt.

It didn't take long for them to be naked and standing together under the water. Mark leaned back against the wall and watched Cristina step fully under the spray. Her thick hair became soaked and he moved forward to smooth his hands over her head and down her body.

"You can touch me if you want." He said softly.

She looked up into his face as she spread her hands over his chest. She smirked. "You take advantage of the gym."

"Free membership does have its perks." He reached to a shelf and picked up a bottle of shampoo, putting a little on her hair and scrubbing it into her scalp.

All he did was wash her body. He did in a kind, respectful way. His hands never ventured between her legs, though he wanted to. He didn't think it was the time or place. He just wanted to be near her.

She took her turn cleansing him, but showed the same respect.

When the soap was washed away, Mark turned off the water and stepped out of the shower. He wrapped a towel around his waist and held out another for Cristina. It was big and fluffy and warm. And it covered her from shoulders to knees.

Mark rubbed her arms and pressed a kiss to her forehead. "I'll leave you to dress in peace."

He walked into his bedroom and was immediately berating himself. She was right there, naked. She was the one who suggested it.

"Mark?" She asked from the doorway.

He turned.

"Did I do something wrong?" She asked softly.

He shook his head. "I'm not ready."

She walked over, tucking the towel under her arms. "It's fine. You want to talk?"

He nodded and sat down on the bed. "I like you. And you are everything I could fall for. I  _have_  fallen for."

"But?" She sat beside him.

"I don't want to push you." He slipped his hand into hers.

"It's not pushing if I want it." She said with a smirk.

Mark watched Cristina a moment and then he rolled into her. He kissed her just as softly as he ever did in the car. His hand rested on her waist. It stayed there.

After a while, Cristina pulled away with a satisfied smile and then curled up against Mark's chest.

Mark's phone went off, interrupting the comfort they both felt, and he reached across Cristina to look at it. A small shocked sound escaped him when he read that it was Kieran.

And then the accompanying text was even more of a surprise.  _Moving to LA. Need to get away from my father._

"Are you okay?" Cristina sat up and watched him.

"My ex…" Mark swallowed and then placed the phone where she could read.

"Oh." She said softly.

"He's just a guy." Mark said softly.

Cristina shook her head. "I can tell it's more than that."

"You and I… We're sort of a thing." He reached out for her.

She curled up against him again. "It's probably best to just be friends. Since we work together."

"Friends who shower together and make out?"

She chuckled. "Sure. As long as your boyfriend is okay with it."

"He's not my…" He sighed. "Okay." He held her in silence until the front door burst open announcing the return of the rest of the Blackthorns.


End file.
